Email Marketing Acronyms: The Complete Guide

July 2, 2020

Understanding vernacular in the digital marketing space can often feel like learning a new language. For email marketers, in particular, the list of acronyms is even longer and more niche. Like any industry, the lessons begin by writing down certain terms here and there to look up later, or attending conferences and grabbing as many brochures and pieces of information to fill in the blanks for you. But with life at a distance and Wikipedia only skimming the surface of certain definitions, wrapping your head around email marketing acronyms and vocabulary can be a bit overwhelming.

A great place to start is by really understanding the acronyms, each step of the way! Below you’ll find some of the most common email marketing acronyms and how they work.

The Basics

ISP: Internet Service Provider

How it works: In email marketing, ISP refers to the major email providers. Similar to Cable TV and telephone networks, there are several household names responsible for providing certain services and they often overlap. It’s the job of the ISP to protect its customers from receiving unwanted or unsolicited emails.

Examples: Verizon, Microsoft, Google, Comcast

When to use it: When you are speaking to a general audience, it’s usually better to avoid naming specific companies. By using the general term ISP, you aren’t singling out one company as being better than another.

ESP: Email Service Provider

How it works: An email service provider is a software service that helps email marketers send out email marketing campaigns to their subscribers. ESPs should offer capabilities to create, build, and segment email subscriber lists, templates, and automatically send emails. After the messages are sent, reports should be provided with detailed analytics on campaigns.

Examples: MailCon partners and other companies like Mailchimp, Phonexa, AWeber, Constant Contact, or Emma.

The Process

Email Marketing Acronyms: The Complete Guide

1. SMTP: Simple Mail Transfer Protocol

In order to transfer your email on and across networks and deliver it to the correct recipients, the first step involves an SMTP transmitting an email through the internet to the MTA. This process is called “store and forward.” Examples of SMTPs include Sparkpost, Mailgun, and SendGrid.

2. MTA: Mail Transfer Agent

Within the internet email system, an MTA is a software that transfers emails from one computer to another using an SMTP. Other common names for an MTA are Message Transfer Agent, Mail Router, or Mail Relay.

3. IMAP and POP3: Internet Message Access Protocol and Post Office Protocol 3

If you’ve ever set up an email address on a new computer or phone, you’re probably familiar with IMAP and POP3. They are both protocols used by MUAs to retrieve and download emails from a server’s mailbox. A key difference to remember is that POP3 is responsible for archiving and deletion, but IMAP maintains and stores all of the emails.

Get Technical: MUA, MSA, & MDA

Using these acronyms similarly allows you to communicate with a larger audience and is solely responsible for the sending of emails. This type of shorthand is useful when you’re avoiding limiting yourself to different e-brands and desktop applications such as Microsoft Outlook or web-based (sometimes also known as Webmail) such as Gmail or Hotmail.

  • Mail User Agent: MUA signifies the computer program or mobile application used to access and manage your emails. These are often also referred to as Inbox Providers, Email Clients, or an Email Reader.
  • Mail Submission Agent: After an email is received, the MSA should check for any errors and transfer the message with an SMTP to an MTA hosted on the same server. Think of this as the holding cell after the send button is clicked, and before it’s opened by the reader.
  • Mail Delivery Agent: This piece of the process stores the message in the recipient’s inbox and is also referred to as a Local Delivery Agent.

For the Marketers

Having a firm understanding of the proper language when it comes to the sending and receiving of emails is important for industry knowledge, but for email marketers, in particular, there are a few key terms to familiarize yourself with.

COI (Confirmed Opt-In) – Like the distinctive coloring of a Japanese fish with a similar name (Koi), the unique link a visitor receives when signing up for an email subscription signifies the same. Not all subscription services contain a confirmation process, but companies are increasingly adding this step into their sign-up requirements.

CTR (Click Through Rate) – Many MailCon partners are email service providers that pride themselves on empowering e-marketers through data and analytics. So if you were to mention click-through rate to any of them, they’re sure to know what you’re talking about. Your CTR is a key performance indicator that easily shows you the percentage of subscribers who are engaged with your efforts.

Now that your vocabulary list is longer, be sure to bookmark this guide to reference when joining in on the next email marketing conference call. Most importantly, you’ll be able to track your own campaigns and understand what’s needed to make the most impact out of your emails.

About the author


Owned and operated by Phonexa, MailCon is a global community that connects marketing professionals with the latest technology, trends, and strategies in email marketing, marketing automation, mobile and omnichannel marketing. Our fantastic team of content writers contribute to this blog with inspiration from the incredible community of marketers we are privileged to host.


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